Count my DD among the scooters! At first she was pretty slow and I figured I could keep up with her getting around the house (and not babyproofing yet). However, this week she has proved me wrong and is into everything - little speed demon! Needless to say - we're investing in the babyproofing supplies this weekend!
I don't know if she'll ever crawl on hands and knees. She's never been a fan of tummy time. We try to put her on her tummy now and she just rolls onto her back anyway. And as of today (!) she can sit herself up from being on her back - getting herself into scooting position...and away she goes!